From http://www.ajc.com/news/atlanta-weather-light-rain-1218833.html
The real chill comes Friday morning. Intown areas will be just above freezing, but the suburbs will drop into the 20s, said Chandley.Basil growers, this is it: last call to harvest, dry or freeze the leaves, or make pesto, or pot your plant and bring it indoors to a sunny, well-insulated window before it turns to mush.